<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>

    <style>
        #div_parent {
            height: 500px;
            width: 500px;
            background-color: aqua;
        }
        
        #div_child {
            width: 300px;
            height: 250px;
            background-color: blueviolet;
        }
    </style>

    <script src="./demo5.js"></script>
    
</head>

<body>
    <div id="div_parent">
        父div
        <div id="div_child">
            子div
        </div>
    </div>
    <div>
        <ul>
            <li>拿铁</li>
            <li>可乐</li>
            <li>果汁</li>
        </ul>
    </div>
    <a href="https://baidu.com">百度</a>


</body>

</html>